Draw tape bags have been known for several years and are described in various references such as, for example, U.S. Pat. Nos. 2,798,523 and 3,029,853. Bags of this type are formed by two pliable plastic sheets joined to one another on three sides and open at a fourth. A tubular hem is provided at the open edge of each sheet and contains a pliable thermoplastic strip. One or more holes in the hem expose the strip or strips, allowing it or them to be pulled through the opening and used as a handle while simultaneously closing the open mouth of the bag.
One conventionally employed method of forming such bags is described in U.S. Pat. No. 3,772,968 to Ruda. There, separate draw tape strips are positioned near either longitudinal side edge of a single, flat sheet of thermoplastic film. The extreme edges of the material are then turned over the strips forming hems. The sheet is medianly folded to bring the hems together in an adjoining relationship. The continuous length of folded film is thereafter transversely heat sealed and severed to form individual bags. One distinct disadvantage of this method of manufacturing and the apparatus employed to practice it is that a relatively large workspace must be provided in order to work with the unfolded sheet of material.
Another method employed for forming string-tied bags is described in U.S. Pat. No. 3,512,456 to Meyer. According to the Meyer patent, a draw string bag is provided by positioning draw strings on the exterior surfaces of a medianly folded length of thermoplastic film near the two longitudinal "free" edges and outwardly folding the free edges over the string to form hems. While this method allows the use of a length of medianly folded thermoplastic film and reduces floor space requirements, it results in a bag having an unsightly exposed hem.